Hairdyeing composition and method

Abstract

Compounds of the formula R--C(R.sup.2)═C(R.sup.3)--C(R.sup.4)═C(R.sup.5)--R wherein R is --CHO, --CH(OR 6 ) 2 , 1,3-dioxolan-2-yl, 4-methyl-1,3-dioxolan-2-yl or 1,3-dioxan-2-yl; R 2 , R 3 , R 4 and R 5 independently are hydrogen, methyl or ethyl; and R 6 is C 1-8 alkyl are highly useful as cosmetic active ingredients, e.g., as hair dyes and skin tanning agents. Compositions of these compounds with other active ingredients such as dihydroxyacetone are also quite effective.

What is claimed is: 
     
       1. A hairdyeing composition comprising an amount, effective to dye hair, of at least one compound of formula II   R.sup.7 --C(R.sup.2)═C(R.sup.3)--C(R.sup.4)═C(R.sup.5)--R.sup.7(II)     wherein   R 7  is --CH (OR 12 ) 2  ; R 12  is C 1-8  alkyl; and R 2 , R 3 , R 4  and R 5  independently are hydrogen, methyl or ethyl;   and an adjuvant acceptable in cosmetics.   
     
     
       2. A composition of claim 1, wherein R 12  is methyl, ethyl, propyl or butyl; and R 2 , R 3 , R 4  and R 5  are hydrogen. 
     
     
       3. A composition of claim 1, wherein the compound of formula II is 1,1,6,6-tetraethoxy-2,4-hexadiene. 
     
     
       4. A composition of claim 1 further comprising dihydroxyacetone. 
     
     
       5. A composition of claim 2 further comprising dihydroxyacetone. 
     
     
       6. A composition of claim 3 further comprising dihydroxyacetone. 
     
     
       7. A method of drying human hair which comprises applying to the hair an amount of a cosmetic composition of claim 1, 2 or 3 effective for dyeing human hair. 
     
     
       8. A method of dyeing human hair which comprises applying to the hair an amount of a cosmetic composition of claim 4 effective for dyeing human hair. 
     
     
       9. A method of dyeing human hair which comprises applying to the hair an amount of a cosmetic composition of claim 5 effective for dyeing human hair. 
     
     
       10. A method of dyeing human hair which comprises applying to the hair an amount of a cosmetic composition of claim 6 effective for dyeing human hair.